1. Field of the Invention
The present invention relates to a coordinate detecting device for inputting coordinates to a computer operating as an external apparatus.
2. Description of the Related Art
In a conventional coordinate detecting device, as shown in FIG. 6, the operation of the coordinate detecting device is checked prior to factory shipment or during a repair in a condition in which the housing thereof is opened, an upper cover 71 is removed, and a circuit board 81 inside is exposed. In a coordinate detecting device having storage elements (e.g., ROMs) in which data used to adjust each apparatus (hereinafter referred to as "adjustment data") stored, the adjustment data are written at a time when the housing is open.
A coordinate detecting device 80 outputs to an external apparatus, such as a computer, the coordinates of a position pointed to by a position pointing device 80 as shown in FIG. 6. Whereas the position pointed to by the coordinate detecting device 80 is located on an effective area 73 on the surface of the housing when in use, that position becomes lower in a condition in which an upper cover 71 of the housing of the device 80 is removed. Therefore, it is necessary to place a plate 90 having a predetermined thickness (hereinafter referred to as a "height compensation plate") in order to check the operating state.
Therefore, in the past, the laborious task of placing the height compensation plate 90 must be performed after the housing is removed to write adjustment data or to check the operation of the device. The height compensated for by the height compensation plate 90 has been assumed to be the same for all of the manufactured devices, and variations from device to device ignored. However, in practice, there are variations in the height of each apparatus resulting from variations in the molded dimension of the housing or from variations in screwing during assembly.